1. Field of the Invention
This invention relates to an industrial truck having a lifting mast with a fixed mast and at least one movable mast that can be extended vertically in relation to the fixed mast. A load lifting device can be moved up and down on the movable mast. On the movable mast and/or on the load lifting device, there is at least one electrical component connected with at least one electrical cable.
2. Description of Related Art
Industrial trucks are known in many different configurations. Electrical components that must be supplied with electrical energy or electrical signals are frequently located on the movable mast and/or the load lifting device. On lifting masts with a large lifting height, such as duplex and triplex masts, electrical cables provided with slip rings can be payed out for this purpose to supply power and signals to the electrical components even in the raised position. Contact resistance thereby occurs disadvantageously at the slip rings. Furthermore, slip rings can be inserted only with certain types of cables, and not at all on cables that require a continuous shielding of the cable conductors (e.g., for cameras having a cable for video signals). Moreover, for space reasons, slip rings can connect only a relatively limited number of cable conductors.